Could you share your events and/or capx, because for now I can only repeat the same answer..

set the amount of pixels per frame lower to reduce the speed..

You might be a lot better of using the bullet behaviour or the move to behaviour or even the 8 direction behaviour to get it done the way you envision, but I wouldn't know, for it is very unclear to me what is and what isn't happening the way you want it..

Maybe checking the x-coordinate on which the sprite is created with it's current x and having the movement depend on that would help..

But really, without further clarification about your events and the expected result, I'm only guessing..